关于exp statistics的问题和简单测试(82天)

[ora11g@rac1 ~]$ exp n1/n1 tables=t file=t.dmp rows=n 
Export: Release 11.2.0.3.0 - Production on Fri May 23 19:26:35 2014 
Copyright (c) 1982, 2011, Oracle and/or its affiliates.  All rights reserved. 
Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production 
With the Partitioning, OLAP, Data Mining and Real Application Testing options 
Export done in US7ASCII character set and AL16UTF16 NCHAR character set 
server uses AL32UTF8 character set (possible charset conversion) 
Note: table data (rows) will not be exported 
About to export specified tables via Conventional Path ... 
. . exporting table                              T 
EXP-00091: Exporting questionable statistics. 
Export terminated successfully with warnings. 

SQL>  select * from v$nls_parameters where parameter='NLS_CHARACTERSET'; 
PARAMETER 
---------------------------------------------------------------- 
VALUE 
---------------------------------------------------------------- 
NLS_CHARACTERSET 
AL32UTF8 
SQL> host

echo的结果不是没设置，就可能是设置的有问题。重新设置，问题就解决了。 
[ora11g@rac1 ~]$ echo $NLS_LANG 
[ora11g@rac1 ~]$ export NLS_LANG=AMERICAN_AMERICA.AL32UTF8 
[ora11g@rac1 ~]$ exp n1/n1 tables=t file=t.dmp rows=n 
Export: Release 11.2.0.3.0 - Production on Fri May 23 19:28:42 2014 
Copyright (c) 1982, 2011, Oracle and/or its affiliates.  All rights reserved. 
Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production 
With the Partitioning, OLAP, Data Mining and Real Application Testing options 
Export done in AL32UTF8 character set and AL16UTF16 NCHAR character set 
Note: table data (rows) will not be exported 
About to export specified tables via Conventional Path ... 
. . exporting table                              T 
Export terminated successfully without warnings.

[ora11g@rac1 ~]$ exp n1/n1 tables=t file=t.dmp rows=n
Export: Release 11.2.0.3.0 - Production on Fri May 23 19:53:24 2014
Copyright (c) 1982, 2011, Oracle and/or its affiliates.  All rights reserved.
Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production 
With the Partitioning, OLAP, Data Mining and Real Application Testing options 
Export done in US7ASCII character set and AL16UTF16 NCHAR character set 
server uses AL32UTF8 character set (possible charset conversion) 
Note: table data (rows) will not be exported
About to export specified tables via Conventional Path ... 
. . exporting table                              T 
EXP-00091: Exporting questionable statistics. 
Export terminated successfully with warnings.

SQL> create table testo.t tablespace pool_data as select *from n1.t where rownum<2;
Table created.
[ora11g@rac1 ~]$ imp testo/oracle file=t.dmp tables=t statistics=always
Import: Release 11.2.0.3.0 - Production on Fri May 23 19:54:01 2014
Copyright (c) 1982, 2011, Oracle and/or its affiliates.  All rights reserved.
Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production 
With the Partitioning, OLAP, Data Mining and Real Application Testing options
Export file created by EXPORT:V11.02.00 via conventional path
Warning: the objects were exported by N1, not by you
import done in US7ASCII character set and AL16UTF16 NCHAR character set 
import server uses AL32UTF8 character set (possible charset conversion) 
. importing N1's objects into TESTO 
. importing N1's objects into TESTO 
Import terminated successfully without warnings.

********** TABLE GENERAL INFO *****************
TABLE_NAME                     PAR TABLESPACE STATUS   NUM_ROWS     BLOCKS EMPTY_BLOCKS LOG MON ROW_MOVE LAST_ANAL 
------------------------------ --- ---------- ------ ---------- ---------- ------------ --- --- -------- --------- 
T                              NO  POOL_DATA  VALID     6856704      39174            0 NO  YES DISABLED 23-MAY-14